This protocol will determine the incidence of Mycobacterium tuberculosis (M tb) infection in HIV-infected and -uninfected injecting drug users (IDUs), sexual partners of IDUs, and children in contact with TB-infected adults. It will identify environmental and host risk factors for developing M tb infection; describe the natural history of M tb disease in children and adults; investigate the epidemiology of specific strains of M tb; evaluate the effect of M tb coinfection on the rate of progression of HIV disease; and investigate factors influencing compliance with tuberculosis prophylaxis and therapy. The lab was used for blood separation, DNA isolation, ELISA, laminar flow hoods, Oligonucleotide synthesis, PCR, and RNA isolation, and recombinant DNA techniques.